1. Technical Field
This invention relates generally to a mechanism for opening, closing and locking railcar doors, and more specifically to a mechanism for opening, closing and locking rapid discharge railcar doors located on or near the bottom of a railcar.
2. State of the Art
A common type of railroad freight car used today is an open-top hopper car wherein the commodity carried by the railcar is discharged through an opening provided on the underside of the car. Such cars are used to haul aggregate, iron ore, coal and other commodities. Such cars offer an advantageously economical method of transporting large amounts of a commodity between locations.
Conventionally, when a hopper car arrives to deliver its load, technicians open its doors. The conventional way to open the door is by striking the railcar door latch in an upward direction with a large sledgehammer. For each door, there is a latch at each side of the door (two latches per door set). The striking motion must be accurate for each latch to move to the open position. Often, it takes multiple strikes of a hammer to release each latch, allowing the doors to open and dispatch the material.
The technician opening the door in this conventional way is exposed to many hazards. The surface he is standing on, through which the transported commodity falls, is generally a grate of various dimensions of spacing; an estimated average is an opening of approximately six inches square. The grate is necessary for the material to flow through to a storage container or hopper located under the grate. The grate creates a hazard for the technician, and the industry has experienced an unacceptably large number of accidents related to human extremities slipping through the grate while technicians open the doors. Additionally, strikes missing the latches while attempting to deliver strikes powerful enough to move the latches can result in the technicians loosing their balance, falling and sustaining various other injuries.
To close the doors, the technician again stands on the grate through which the material flows. While on this grate, the technician is required to insert a heavy steel bar through a rung on the car hopper door, and then pry the door up to the latch of the railcar door. This action is repeated for each side of each door set. When the hopper doors are bent or out of square, which is common because the doors are generally opened one side at a time causing torsional stresses on the door from the weight of the commodity above the door, the technician is required to use additional force to bend the doors closed. This action while standing on the grate creates additional hazards for the technicians, and the industry has experienced an unacceptably large number of accidents related to human extremities falling through this grate while technicians close the doors. Many back injuries are also sustained.
Accordingly, what is needed is a mechanism that will open and close a railcar door with limited or no technician intervention and will replace the currently difficult and dangerous to operate door latches.